Triathlon Heart Rate Zones Calculator
Calculate heart rate training zones for triathlon.
Set Zone 1-5 targets from your max heart rate for optimal triathlon training.
Heart rate zones define exercise intensity levels. Training in each zone produces different physiological adaptations. Triathlon training uses all five zones, but the bulk of base-building volume (especially for long-course racing) should be in Zones 1–2.
Standard 5-zone model (% of max HR):
- Zone 1 (50–60%): Active recovery. Feels very easy. Promotes blood flow.
- Zone 2 (60–70%): Aerobic base. Can hold a conversation. Fat burning. Long-course triathlon target zone.
- Zone 3 (70–80%): Tempo. Comfortably hard. Threshold development.
- Zone 4 (80–90%): Lactate threshold. Hard but sustainable for 20–60 min. Race pace for Sprint/Olympic.
- Zone 5 (90–100%): VO2 max / neuromuscular. Maximum effort. Only used in intervals.
Finding max heart rate:
- Estimate: 220 − age (rough, ±10–15 bpm for many people)
- Accurate: Field test (e.g., 3×800 m run all-out, record highest HR)
Resting heart rate: Measure first thing in the morning before getting out of bed. Trained endurance athletes often have resting HR of 35–50 bpm.
Heart Rate Reserve (Karvonen) method: HRR = Max HR − Resting HR Target HR = Resting HR + (HRR × zone percentage)
This personalises your zones more accurately than simple percentage of max HR.
Long-course triathlon pacing: Ironman bike is typically 70–80% of max HR (Zone 2–3). Ironman run is 75–80% max HR. Going above Zone 3 on the Ironman bike almost always results in a painful run.